The present invention relates to biosourced fatty acid polyester derivatives of polyglycosides, the preparation process and use thereof as synthons in the preparation of different materials.
Synthetic polymers form part of daily life. Light, strong, insulating, easy to use, they are utilized in sectors as diverse as construction, packaging, the electrical and electronics industry, electrical goods, the toy sector and transport (automobile, railway, aeronautical, etc.). The limited and fossil nature of petroleum resources and considerations relating to the quality of the environment (global warming, waste management) provide a genuine opportunity for biosourced polymers, namely no longer originating from petroleum but from biomass.
Among these polymers, the epoxy resins, through their physico-chemical properties (mechanical, electrical, etc.) constitute a versatile class of thermosetting polymers that are very widely used in the fields of electronics, construction, paints or also transport. The vast majority of those currently on the market are of petrochemical origin. They are formed by mixing one (or more) “epoxy prepolymer(s)” (in other words a molecule bearing epoxy reactive groups) with a hardener also denoted by the term “cross-linking agent”. These two families of components (prepolymer and hardener) react together by polymerization which, depending on the functionality of the chemical species involved, can generate the production of a three-dimensional polymer network. The epoxy resins are then referred to as cross-linked.
Many epoxy formulations make use of a prepolymer sourced from oil, bisphenol A diglycidyl ether (or BADGE). Now the latter is formulated from bisphenol A which is a compound classified as CMR (carcinogenic mutagenic reprotoxic). Its epoxidation is itself open to criticism on health grounds as it makes use of epichlorohydrin, the chemical toxicity of which is currently a subject of debate and the use of which is itself likely to be restricted or even discontinued in the medium term.
Thus, in order to find a response to increasingly stringent regulatory restrictions (REACH, RoHS, etc.) as well as facing up to the inevitable exhaustion of petroleum resources, diverse research has been carried out in order to try to develop materials, notably polymers, in particular epoxy resins, originating from biomass.
Thus the inventors have described, in application WO 2013/124574, epoxy resins comprising the product of the reaction of one or more biosourced epoxidized lipid derivatives extracted from a natural vegetable oil, with at least one cross-linking agent, in the presence of at least one co-reagent selected from the glycidyl ether derivatives of biosourced polyols.
The inventors have subsequently sought, on the one hand to further enhance the performances of these biosourced resins, in particular in terms of the glass transition temperature, and on the other hand to develop a versatile approach allowing the creation of platform molecules with chemical characteristics (nature and number of functionalities) allowing a wide range of forms ((polyepoxy, polyamine, polyols etc.) and therefore of potential applications.
French patent FR2962131 describes fatty substances of natural origin functionalized with primary alcohol functions or primary amine functions by a reaction of the thiol-ene type and use thereof in order to prepare, by polycondensation, polymers of different types: polyamides, polyurethanes, epoxy resins.
U.S. Pat. No. 6,995,232 describes the synthesis of sucrose polyesters (SEFOSE) by the reaction of individual fatty acid esters with sucrose. The final structure is thus formed by a saccharide-type core (a glucose ring “naturally” linked to a fructose ring) onto which up to eight fatty chains (SEFOSE) are grafted.
International application WO 2011/097484 describes the functionalization by epoxidation of the SEFOSEs described by U.S. Pat. No. 6,995,232 and international application WO02/060975. Strictly speaking, the chemical concept proposed relates only to the so-called epoxidation phase and allows no modulation of the central core of the initial molecular structures that is however essential to versatility of function and use.
However, there is still a need to have versatile molecular structures available, in order to allow the manufacture of materials that are partially or completely biosourced and having a wide range of mechanical characteristics, in particular in order to compete with those of the polymers of petrochemical origin and in order to adapt to numerous functions of final use.